May 27, 2020

This post is part of a multi-part series about pre-filled syringes. Find the first post in the series, ‘Five Ways Pre-filled Syringes Contribute to Better Patient Outcomes,’ here.

The pre-filled syringe (PFS) space is one of the fastest growing pharma sectors, expected to be worth $9.7bn by 2025, or 9% CAGR. Compared with traditional vial delivery systems, PFS offers greater patient safety and lower manufacturing costs – but pre-filled doesn’t translate to easily filled. The increase in biologic drugs – driving the PFS boom – presents particular obstacles, primarily attributed to viscosity.

AMRI PFS LINE IN ALBUQUERQUE, NM
AMRI PFS LINE IN ALBUQUERQUE, NM

Overcoming Viscosity

Different products have differing viscosity, or centipoise levels, requiring unique processing solutions. A major challenge is cleanly dispensing product into the syringes, as product will often stick to the tip of the filling needle and create a trail of product along the syringe after dispensing.

CDMOs must work with both clients and equipment manufacturers to overcome such challenges, necessitating product-centric solutions and high levels of expertise. For example, collaborative efforts with key equipment vendors were conducted at AMRI’s Albuquerque, NM facility to engineer, reprogram, and test the Programmable Logic Controller (PLC) logic for the motion and timing of the fill curve, allowing for better process parameter predictability of the equipment.

Controlled Processes

Handling controlled substances is another challenge intensified by viscosity.

A robust reconciliation process is needed to track and trace batches to quantify the controlled substance employed. At AMRI, compliance managers account for product usage levels from start to final packaging, including product quantity used in preparation and flushing of production lines. Such robust processes are critical in assuring compliance and successfully clearing rigorous DEA auditing.

Glass vs. Polymer

PFS CDMOs must remain mindful of new technologies and the evolving PFS landscape. When it comes to product material selection, we provide client support by taking into account the end user, administration, and manufacturing of the product.

At AMRI we’ve seen an increasing demand for plastic but selection rests on more than the inherent properties of the base materials being filled. Glass prevents water vapor and oxygen from interacting with the product, but is more susceptible to extractables and leachables, as well as breakages. Polymer syringes are free of heavy metals and tungsten but are easily scratched and not ideal for oxygen-sensitive drugs.

AMRI’s in-house analytical team expert in extractables and leachables, container testing, and heavy metal detection, significantly aids in optimizing container closure design for a given product and is a valuable resource for our clients.

Shared Risk

Many CDMOs are also developing service models focused on resource flexibility and shared risk. With 30 years of FDA audits, AMRI, for example, demonstrates an impeccable track record in product quality, on-time delivery, regulatory compliance, safety, and value – all of which a CDMO must offer in competitive outsourcing.

Having completed media fills and scaled up commercial manufacture for two existing lines, AMRI can offer the highest level of Current Good Manufacturing Practices (CGMP) aseptic processing and enable pre-approval inspections (PAI) for commercial products, transferring capabilities at speed to new commercial drug product manufacturing requirements.

One-Size-Doesn’t-Fit-All

There is no one-size-fits-all approach for PFS manufacturing. Of course, CDMOs must integrate the latest technology and implement fail-safe compliance processes, but that’s only the beginning. Success relies on product characterization, processing, and an understanding of equipment range to ensure unique needs are met and drive true partnership with clients.


AMRI offers comprehensive sterile dosage form development and manufacturing services including best-in-class prefilled syringe manufacturing capabilities. Our state-of-the-art prefilled syringe production lines utilize Restricted Access Barrier System (RABS) technology and other automation to ensure the highest level of sterility assurance and product yields for your valuable injectable medicine.

Learn more about our FDA-inspected, cGMP-compliant facility for clinical or commercial scale manufacturing today!

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